Apple Hardware Test

In this video, I show you how to run the Apple Hardware Test. This test is for Macs older than June of 2013.
IMPORTANT: If your Mac was released after June 2013, you will use Apple Diagnostics rather than Apple Hardware Test (AHT). See Apple Diagnostics below for instructions.
Isolating issues in Mac OS X (to hardware or software)
http://support.apple.com/kb/TS1388
Apple Hardware Test
http://support.apple.com/kb/ht1509
Apple Diagnostics
http://support.apple.com/kb/HT5781
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